A data communications network generally includes a group of devices, for instance, computers, repeaters, bridges, routers, etc., situated at network nodes and a collection of communication channels for interconnecting the various nodes. Hardware and software associated with the network and particularly the devices permit the devices to exchange data electronically via the communication channels.
The size of networks varies. A local area network (LAN) is a network of devices in close proximity, typically less than one mile, and usually connected by a single cable, for instance, a coaxial cable. A wide area network (WAN) is a network of devices which are separated by longer distances, often connected by, for example, telephone lines or satellite links. In fact, some WANs span the U.S. as well as the world. Furthermore, many of these networks are widely available for use by the public, including commonly universities and commercial industries.
A very popular industry standard protocol for data communication along the networks is the Internet Protocol (IP). This protocol was originally developed by the U.S. government's Department of Defense, and has been dedicated for public use by the U.S. government. In time, the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) were developed for use with the IP. The former protocol (TCP/IP) is a protocol which guarantees transfer of data without errors, as it implements certain check functionality, and the latter protocol (UDP/IP) is a protocol which does not guarantee transfer of data, but requires much less overhead than the TCP/IP platform. Furthermore, in order to keep track of and manage the various devices situated on a network, the Simple Network Management Protocol (SNMP) was eventually developed for use with a UDP/IP platform. The use of the foregoing protocols has become extensive in the industry, and numerous vendors now manufacture many types of network devices which can employ these protocols.
Management stations are connected to a network and are configured by a management software package to discover the network topology. The network topology generally includes the network nodes and node interconnections existing on the network. From the network topology, the station constructs a network management map, which comprises a collection of various submaps. Each submap corresponds with a different view of the network and any can be driven to a display device. Typically, the submaps are arranged in a hierarchy.
As an example of a network management map, consider the following possible implementation, which has been implemented in the past in the well known "OPENVIEW".TM. management software, which is manufactured by and commercially available from the Hewlett-Packard Company, U.S.A. The map has a root submap defined at a root level. The root submap represents the highest logical level submap in the hierarchy and shows objects acting as anchor points for different submap hierarchies. Each hierarchy is essentially a separate management domain. This could be, for instance, a network, logical grouping of nodes, or some other domain. An internet submap is defined at an internet level and is generated by "exploding" an object within the root submap. "Exploding" in the context of this document means that the user prompts the station with an input device to break down and provide more data pertaining to an object at issue. Further, the internet submap illustrates objects in the form of networks and routers. Any one of a number of network submaps can be exploded from the internet submap. Each network submap shows objects in the form of segments and connectors. Any one of a number of segment submaps can be exploded from an object within a network submap. Each segment submap shows objects in the form of network nodes. Finally, any one of a number of node submaps can be exploded from an object within a segment submap. Each node submap shows objects in the form of interfaces within that node.
Hewlett-Packard's "OPENVIEW".TM. management software has been the subject of several patents, including for instance, U.S. Pat. No. 5,185,860 issued to J. C. Wu on Feb. 9, 1993, and U.S. Pat. No. 5,276,789 issued to Besaw et al. on Jan. 4, 1994. U.S. Pat. No. 5,185,860 describes an automatic discovery system for a management station for determining the network devices and interconnections of a network, or the topology. U.S. Pat. No. 5,276,789 describes a graphic display system for a management station for graphically displaying the topology of a network and provides for various views (including, internet, network, segment, and node views) that can be requested by a user.
Although the presently available SNMP management stations and related software are meritorious to an extent, the art of SNMP management is still in a state of infancy, and the performance of these management stations and software can still be enhanced and optimized. A specific area where optimization is envisioned involves the discovery mechanism, which monitors and manages the network and systems connected on the network. In many management schemes, monitoring of the network originates from a single management station, no matter how large or geographically distributed. This was the practice in Hewlett-Packard's "OPENVIEW".TM. management software as is described in, for example, U.S. Pat. No. 5,185,860 to J. C. Wu.
Unfortunately, this operation methodology is problematic to an extent and inhibits optimal performance. It limits the number of nodes that can be monitored because of limited system resources. It results in large amounts of traffic over expensive connections. Moreover, if multiple sites within the environment want data about the entire network, each site must directly monitor the entire network itself. No sharing of data occurs.